Abstract: A fast vortex method for solving complex irregualr regions is developedin the present paper, using combination of capacitance matrix technique(CMT), fast Fourier transforms (FFT) as well as vortex-in-cell method (VIC). Using this fast solver, separated flows about a plat flate normal to incoming flow with any thickness and a wedge are, impulsed or accelerated motion from rest, computed at high Reynolds numbers. Expecially, the fine field patterns are obtained around the plat flate flow. Due to Kelvin-Helmho...